The present invention relates to an organic EL device, and, more particularly, to an organic EL device having a multi-layered structure in which a desiccant is incorporated.
An organic EL display device comprises a substrate, a plurality of gate signal lines (scanning signal lines), extend in an x-direction and are juxtaposed in a y-direction transverse to the x-direction, on one of principal surfaces of the substrate, a plurality of drain signal lines (video signal lines), which extend in the y-direction and are juxtaposed in the x-direction, on the one of the principal surfaces of the substrate, and a plurality of pixel regions, each surrounded by a respective pair of the plurality of gate signal lines and a respective pair of the plurality of drain signal lines. Each of the pixel regions is provided with at least a thin film transistor, which is turned on in response to a scanning signal received from one of the gate signal lines, and a light emitting layer (an organic EL layer) to which an electric current is made to flow in response to a video signal supplied from one of the drain signal lines to the each pixel region through the thin film transistor.
Further, in view of a fact that the characteristics of the light emitting layer deteriorate due to oxidation or moisture, usually, another substrate, which differs from the above-mentioned substrates and which blocks the light emitting layer from the outside air, is provided, and a desiccant is arranged in the inside of a space which is blocked from the outside air.
Further, although these respective substrates are made of glass, for example, substrates which are formed of resin have been known recently. Further, there is also a known organic EL display device which has flexibility. In particular, there is a known organic EL display device having a multi-layered structure in which a desiccant is incorporated into a substrate having flexibility, and in which the substrate adopts the desiccant as one layer (see the following patent literatures 1-4).
[Patent Literature 1] Japanese Unexamined Patent Publication 2000-260847
[Patent Literature 2] Japanese Unexamined Patent Publication 2000-348849
[Patent Literature 3] Japanese Unexamined Patent Publication 2001-102167
[Patent Literature 4] Japanese Unexamined Patent Publication 2000-173766